.

What was it?  I cannot see any sale for BIN in your history.  The only one that I can see sold on the 28th and it had 6 bids, and FB was left.

Personally, I would have told the buyer (through eBay message) that I do not post internationally, but if they really insist the postage will be $500.  If they leave NEG, I am sure eBay will remove it considering that they should not have bid on item that is listed as posting to Australia only.